Friends took to social media to express their shock at his passing, with many describing him as a man with a passion for Belfast who will be sadly missed.

The suddenness of his passing surprised many, with friends saying they had spoken to him in recent weeks.

Many told tales of his generosity and warm sense of humour and how he had helped them out at various moments in their lives.

Comedian Tim McGarry said on Facebook: "Genuinely shocked by this. We only worked with Mark half a dozen times but he was a real tour de force and a total joy to be around." Others have spoken of Mr Mearns' larger-than-life presence in the arts scene in and around Belfast's Cathedral Quarter.

Andy Keil said on social media: "It's been a difficult weekend, those of us who knew Mark was ill are having a different experience to those to whom it is a great shock. Different yet equal manners of grief.

"I'm just glad he isn't suffering any more and that he passed away at home with those that he loved.Everyone who knew him has a story about his generosity of spirit. I will miss his enthusiasm.

"Thank you to those who did everything for him as he slipped away, the hospital staff, my colleagues, his friends.

"Indeed if friends are the measure of a man, then Mark was quite a man."

Adrian Power said Mark "was one of the most, positive, funny, loveliest men I have ever known... the world is a little bit dimmer in his passing and my life a little sadder."

Angi Mann said: "Such a nice guy. He was a true gentleman."

Richard Kerr said Mr Mearns "had a wicked sense of mischief and always greeted me with a massive smile and a hug".

Tracey Dempsey said: "Goodbye Mark Mearns. So shocked at the news. I never met a character like him - so kind and generous."

Miriam Crozier said: "Cannot get my head around someone so irrepressible not being here."